Pulsator operated releaser for a pipeline milker



Dec. 21, 1965 R. K. PATTERSON 3,224,413

PULSATOR OPERATED RELEASER FOR A PIPELINE MILKER Filed Jan. 3, 1963 3 Sheets-Sheet 1 INVENTOR ROBERT K. PATTERSON BY 5M ATTORNEY:

Dec. 21, 1965 R. K. PATTERSON 3,224,413

PULSATOR OPERATED RELEASER FOR A PIPELINE MILKER Filed Jan. 5, 1965 3 Sheets-Sheet 2 Fzgi I06 loz/ 15o--. 152" I00 I EL/ I04 108 INVENTOR ROBERT K. PATTERSON ATTORNEY/2S Dec. 21, 1965 R. K. PATTERSON PULSATOR OPERATED RELEASER FOR A PIPELINE MILKER 3 Sheets-Sheet 5 Filed Jan. 3, 1965 INV EN TOR ROBERT K. PATTERSON ATTORNEY/7' United States Patent 3,224,413 PULSATOR QPERATED RELEASER FOR A PIPELHNE MILKER Robert K. Patterson, RED. 3, Montague Road, Amherst, Mass. Filed Jan. 3, 1963, Ser. No. 251,461 3 Claims. (Cl. 1114.07)

This invention relates to improvements in vacuum type liquid pumps, pump washers and control means therefor and is a continuation-in-part of my application Serial No. 122,686 filed July 10, 1961, now abandoned.

The invention has particular utility in milk handling equipment as the pump has a minimum of moving parts, may be readily cleaned and sterilized along with the milk conveying conduits; and the vacuum type liquid pump may be advantageously constructed of glass whereby the operator may have continuous visual inspection of the pump during operation and during cleaning and sterilization.

It is a further object of the present invention to provide in a vacuum type liquid pump improved flow control means which, while positively preventing upward flow of liquids in the system, are gravity opened, readily cleanable, and substantially free from mechanical failure.

A further object is to provide such a device and timer means therefor including an automatic check valve which prevents overfilling of the drain tank and automatic release of the collected liquid from the drain tank in the event of failure of the time controlled actuator for the improved pump.

A further object is to provide an improved control mechanism for the vacuum type liquid pump and washer which provides for a predetermined drain time, a readily variable pumping period and a controlled eflicient wash cycle.

A further object of the present invention is to provide a vacuum type liquid pump, pump washer and timer means therefor that may be readily manufactured and is relatively inexpensive.

These and other objects and advantages are provided in the improved vacuum type liquid pump comprising a container having an upper end 'and a lower end, first conduit means connecting the upper end of the container to a source of reduced pressure, second conduit means connecting said container to a source of liquid, a drain tank having an upper end and a lower end, third conduit means connecting the lower end of the container to said drain tank, fourth conduit means connected to the upper end of the drain tank, fifth conduit means connected to the lower end of the drain tank, a constriction in said third, fourth and fifth conduit means defining a circular opening, a freely-suspended resilient member having a surface larger than the circular opening in said third, fourth and fifth conduit means and adapted to contact the respective circular openings therein to provide a valve in each of said third, fourth and fifth. conduit means, means projecting into said third, fourth and fifth conduit means to support the respective members at a position below their position of contact with their circular openings, thereby providing a check valve in said third, fourth and fifth conduit means against upward flow of fluids, a control valve in said fourth conduit means and positioned on the outlet side of the check valve provided in said fourth conduit means for selective connection to a source of reduced pressure and to atmosphere, and an electrical timer for selective timed actuation of said control valve for alternately connecting said drain tank to the source of reduced pressure and to the atmosphere.

The invention will be more particularly described with reference to the illustrated embodiments thereof shown in the accompanying drawings wherein:

FIG. 1 is a fragmentary partial sectional view of an improved vacuum type liquid pump embodying the features of the present invention;

FIG. 2 is an enlarged fragmentary view of the time control valve for the pump shown in FIG. 1 including a schematic view of a preferred form of electrical control means for selective timed actuation of the control valve; and

FIG. 3 is a fragmentary partial sectional view, similar to FIG. 1 of a modified form of the present invention.

Referring to the drawings, 10 generally designates an improved vacuum type liquid pump embodying the structures of the present invention. The pump 19 includes a container 12 having three ports 14, 16 and 18 communicating with the interior thereof.

Port 14 connects to a conduit 20 which communicates with the source of liquid to be pumped and which, in the preferred embodiment of the invention, is connected to a source of milk (not shown in the drawings).

Port 16 of the container 12 has connected thereto a further conduit 22 which connects the interior of the container 12 and a source of vacuum generally designated by the reference character V. The port 16 and its connected conduit 22 are positioned in the uppermost portion of the container 12.

The port 18, positioned in the lowermost portion of the container 12, has connected thereto a conduit 24. The extended end 26 of the conduit 24 is connected to a second container or drain tank 28. Interposed in the conduit 24 between container 12 and drain tank 28 is a one-way check valve generally designated 30. The check valve 30 is of the type whereby liquids can only pass from the container 12 to the tank 28.

Drain tank 28 is provided with three ports 32, 34 and 36. Port 32 communicates with the extended end 26 of conduit 24 while port 34 is connected to a further conduit 38. Port 34 is positioned in the lowermost portion of the drain tank 28 and corresponds in position to the port 18 of container 12. The extended end of conduit 38 is connected to a suitable storage container for the liquid or directly connected to further processing machinery not forming a part of the present invention.

Port 36 of drain tank 28 is positioned in the uppermost portion of the drain tank 28 and is connected to a conduit 40.

Conduit 38 has interposed therein, between the outlet port 34, and the storage container for the liquid being pumped, a one-way check valve generally designated 42. The check valve 42 is similar to check valve 30 and is of the type wherein liquids will only pass from the container 28 to the receptacle for storing or processing of the liquid being pumped.

The extended end 44 of conduit 40, connected to port 36 of drain tank 28, is provided with suitable time controlled valve means generally designated 46. In the illustrated form of the invention, time control valve means 46 includes a solenoid actuated three-way valve with the solenoid having connection to an electrical circuit generally designated 48 and illustrated in detail in FIG. 2 of the drawings. One of the ports of the three-way valve is connected to a source of vacuum V through. conduit 51) while at the other position of the three-way valve means 46 the container 28 is connected to atmosphere through conduit 52. With this arrangement, the container 28 is alternately connected to the source of vacuum and then to the atmosphere as to be more fully described hereinafter.

In the illustrated form of the present invention, there is provided a one-way check valve generally designated 54 between the outlet port 36 of drain tank 28 and the solenoid-actuated time controlled valve means 46. Thecheck valve 54 is like check valves 30 and 42 and is of the type wherein liquids are prevented from. flowing from the drain tank 28 to the solenoid-actuated time controlled valve means 46.

One-way check valves St), 42 and 54 are each illustrated as including a constriction 56a, b and c, respectively, which constrictions define circular openings in their respective conduits 24, 38 and 41). Cooperating with each of the constrictions is a freely suspended, preferaby resilient, member illustrated in the drawings as plastic spheres 58a, 58b and 58c, respectively. The diameter of the spheres is larger than their cooperating circular openings 56a, 56b and 566 so that when the freely suspended members are urged into contact with the respective circular openings, they provide one-way check valves in their conduits.

Each of the check valves 30, 42 and 54 also includes means 60a, 6% or tic projecting into conduits 24, 38 and 41) to support the respective suspended resilient members 58a, 58b and 580 at positions below their position of contact with their circular openings. While in the drawings each of the forms of the projecting means is different, all three of the valves 30, 42, 54 may have an identical form of projecting means and/or constric tion forming means without efliecting the operation of the valves of the improved vacuum type liquid pump.

Where the improved pump is utilized in handling dairy products, such as milk, it is advantageous to construct the container 12, the drain tank 14, conduits 20, 22, 24, 33, and 40 of glass, such as Pyrex glass. Constructing these items of glass permits the operator to observe the functioning of the pump and permits visual inspection of the members of the pump following cleaning as a further aid in insuring contamination-free handling of milk products. Further, the smooth, open form of the check valves 3t), 4-2, and 54 is instrumental in maintaining contamination-free pumping of milk as the valves are readily cleaned as to be more fully described hereinafter.

Referring particularly to FIG. 2, there is shown a preferred embodiment of the timer mechanism for energizing the solenoid-actuated three-way valve means 46 connected to conduit 40 on the outlet side of one-way check valve 54. As hereinbefore discussed, the solenoid-actuated three-way valve 46 has one connection to the conduit 40, one connection to the vacuum line 50 and one connection to the atmosphere through line 52. The solenoidactuated valve is of the conventional type and spring urged to a position wherein the vacuum line 50 is in communication with conduit 46 and urged by electrical current in the other position wherein atmospheric pressure through line 52 is connected to conduit 40. The solenoid (not shown) of the solenoid-actuated valve 46 is connected to a pair of leads 1G0 and 102 which in turn are connected to a source of alternating current 104 through the electronic timer circuit 43. The timer circuit 43 includes a rectiher 106, a fixed resistance 107, a variable resistance 108, a normally closed relay operated switch 110, a condenser 112, a cold cathode discharge tube 114 with the grid of the tube connected across the condenser 112 through resistors 116, 118 and 120. The positive side of the tube 114 is connected to line 100 through conductor 122 while the negative side of the tube 114 is connected to the opposite side of the condenser 112 through line 124 which line includes therein a relay 126, which relay, when energized, opens normally closed switch 110 and closes a pair of normally open switches 128 and 130. Normally open switch 128 is in parallel with tube 114 and switch 130 is interposed in line 190 between the source of current 104 and the solenoid of the solenoid-actuated switch 46.

The system may also include a pair of fuses 132 and 132.

In a preferred embodiment of the timer mechanism, the various elements thereof having the values indicated in the following chart, has been found to be very accurate, dependable and have a long life:

Item: Value Rectifier 150 M.A. Silicon Type Resistor 107 .5K Variable Resistor 108 10K Condenser 112 300/LF.

Resistor 116 150K Resistor 118 K Resistor 1'20 70K Tube 114 0A4G Relay 126 6.5K

In operation of the invention, conduit 21) is connected to a source of milk, conduits 22 and 50 are connected to source of vacuum of about 15 inches of mercury and the timer mechanism 48 is energized by volts alternating current. At the beginning of the cycle, the solenoid of the solenoid-actuated valve 46 is unenergized whereby a reduced pressure is drawn on both the container 12 and the drain tank 28. By way of example, each of these containers has a capacity of 22 liters with an inside diameter of about 13.7 inches.

The vacuum applied to container 12 draws milk through conduit 21) into the container 12 which milk passes about the suspended resilient member 58a, flows by gravity down conduit 24 into the drain tank 28. Since a vacuum is also being drawn on drain tank 28, freely suspended resilient member 58b of one-way check valve 42 is in sealing engagement with the circular opening 56b of the valve and the container drain tank 28 begins to fill with milk. The freely suspended resilient member 580 of one- Way check valve 54 is at a rest position against projection 60c and would not move to the closed position until the drain tank 28 is filled and the freely suspended member 580 is carried by the milk into sealing engagement with the circular constricted opening 560. This action only occurs where the timing cycle is not properly regulated. During this portion of the pumping cycle, the rectified current passing through rectifier 106 charges the condenser 112. When the charge on the condenser 112 is large enough to cause the cold cathode tube 114 to fire, current flows through lines 122 and 124, energizing relay 126. The energization of relay 126 opens normally closed switch 110 and closes normally open switches 128 and 130.

With switch 130 closed, current from the source 104 energizes the solenoid of solenoid-actuated three-way valve 46 which cuts off the supply of reduced pressure to the drain tank 28 and connects the conduit 40 of the drain tank to the atmosphere through conduit 52. As soon as the drain tank 28 is vented to atmosphere, freely suspended resilient member 53b of check valve 42 is urged downwardly into contact with projection 60b whereby the milk in the drain tank 28 flows therefrom. Simultaneously, the vacuum being drawn on container 12 via conduit 22 urges the freely suspended resilient member 58a of check valve 30 into engagement with the circular opening 56a of the constricted portion of the check valve, preventing further flow of milk from the container 12 to the drain tank 28. This portion of the cycle continues as the relay 126 remains energized as the energy stored in the condenser 12 is discharged through now closed switch 128 to the relay 126 via line 124. The relay 126 thus remains energized during a change of energy level of the condenser 112. When the energy level of the condenser 112 drops below that necessary to energize the relay 126, the de-energized relay permits normally open switches 128 and 131) to open and normally close switch 110 to return to the closed position whereby rectified current then proceeds to recharge the condenser 112. As soon as the relay 126 is un-energized and switch 130 opens, the solenoid of three-way solenoid valve means 46 becomes unenergized and thus drain tank 28 is again connected to the source of vacuum through conduit 50. Under these conditions, it has been found that the pump will deliver about 9 gallons of milk per minute.

The time it takes to energize the condenser 112 in the timer circuit is determined by the supply voltage and the variable resistance 108. Thus, by changing the resistance in the variable resistance 108, the charging time of the condenser may be varied over a substantial range and with the values set forth herein, the charging time may be varied from about 1 to about 60 seconds. The time that the relay coil remains energized after the con denser is charged to cause cold cathode tube 114 to fire is fixed for a given capacitance of the condenser 112. By varying the capacitance of the condenser draining times of 1 to, for example, 20 seconds may be readily obtained.

When it is desired to wash the apparatus, the vacuum line is removed from conduit 22 connected to container 12 and the conduit is connected to suitable wash tanks by a flexible hose; under these conditions, the pump will deliver about 15 gallons per minute. This maximum capacity during washing is desirable for the best cleaning action.

It will be apparent to those skilled in the art that where a greater pump capacity is desired, larger conduits 24 and 38 are provided in the system and the one-way check valves 30 and 42 are correspondingly increased in size.

From the foregoing description of the improved vacuum type liquid pump and control means therefor, it will also be apparent to those skilled in the art that the objects hereinabove set forth are fully accomplished and that various modifications may be made in the form of the invention without departing from the scope thereof as defined in the appended claims. For example, the solenoid-actuated three-way valve 46 may be readily replaced by a pair of two-way solenoid-actuated valves with one of the valves controlling the flow of reduced pressure from conduit 50 to the drain tank 28 which solenoidactuated valve is normally open and is connected across lines 100 and 102 with a normally open relay operated switch 130 interposed in one of the lines as illustrated in FIG. 2. The other solenoid operated two-way valve 150 would connect the drain tank 28 to atmosphere through a normally closed valve and the solenoid actuator for the valve would be connected to the source 104 of alternating current through conductors 152 and 154 having interposed therein a normally closed switch 156 actuated by the relay 126.

It will be further appreciated that conduit 22 may be provided with a flow control check valve such as indicated at 72 in FIG. 1.

Flow control check valve 72 would prevent flooding of the vacuum system in case the liquid flow exceeds the capacity of the container 12 or if the fill cycle of the automatic time control valve is improperly adjusted.

Suitable operation of the improved vacuum pump and timer would also be provided by connecting the milk, or other liquid, inlet conduit 20 to conduit 24 on the container 12 side of flow control check valve 30 instead of connecting the conduit 20 directly to container 12 as illustrated in phantom lines at 211' in FIG. 1 of the drawings.

Further, Where desired, the lower end 26 of conduit 24 may be tangentially connected to the drain tank 25. The tangential connection has been found to reduce turbulence and agitation of the liquid being pumped.

Referring to FIG. 3 of the drawings, 10' generally designates a modified form of the improved vacuum type liquid pump embodying the structures of the present invention. The pump 10' includes a container 12' having two ports 16' and 18' communicating with the interior thereof.

Port 18' of the container is connected to a conduit 20' through conduit 21 and a manually controlled valve 6 generally designated 23. The conduit 20' has connected thereto a further conduit 25 which is connected to a source of liquid to the pump which in the preferred embodiment of the invention is a source of milk designated by the letter M. The conduit 25 is provided with a manual shut-off valve 27.

Conduit 26" also is provided with a plurality of branch conduits designated 3111, b and c. Each of the branch conduits 31a, b and c is provided with a removable closure cap 33a, b and c, respectively, for the purposes to be more fully described hereinafter. Further, conduit 20 has connected thereto a solenoid-actuated valve structure 29 which is normally closed and upon opening of the solenoid actuated valve 29, the conduit 20' is vented to atmosphere.

Port 16' of container 12' has connected thereto a further conduit 22' which connects the interior of the container 12' and a source of vacuum generally desig nated by the reference character V. A self-draining trap 35, a manual control valve 37 and a vacuum regulator 39 are interposed in the conduit 22' between the source of vacuum V and the container 12'.

The self-draining trap 35 includes a bottom drain member 41 having a one-Way check valve 43 therein. The check valve 43 includes a 'ball member 45 which is urged by gravity into an inactive or drain position as illustrated in FIG. 3 and, upon application of a vacuum to the trap, the ball 45 is drawn upwardly into sealing engagement with the valve seat means 47. The trap includes a further check valve structure generally designated 49 and includes a spherical element 51 which is urged by gravity into the valve open position illustrated in FIG. 3 and is urged upwardly into the valve closed position only if the liquids being pumped flow into the trap 35 to a level whereby the spherical element 49 would float into sealed engagement with the valve orifice 53. Thus, check valve structure 49 prevents the flow of fluids being pumped into the vacuum lines in the event of malfunctioning of the pump system.

The vacuum regulator 39 is of conventional design and is preferably of the controllable type whereby air is bled into the system if the vacuum drawn within the conduit 22' is greater than a pre-set amount. In the normal operation of this form of the invention, the vacuum regulator would be set to function at, for example, 1 to 3 inches of mercury, at the manual control valve 23 hereinbefore described.

The valve 23 connects conduit 21 at the lower end of container 12' to a conduit 24. The conduit 24' is connected to a second container or drain tank 28'. Interposed in the conduit 24 between the valve 23 and the drain tank 28' is a one-Way check valve generally designated 30. The check valve 30 is of the type whereby liquids can only pass from the valve 23 side of conduit 24 into the drain tank 28.

Drain tank 28' is provided with three ports 32, 34 and 36'. Port 32 communicates with the extended end of conduit 24' while port 34' is connected to a further conduit 38. Port 34' is positioned in the lowermost portion of the drain tank 28' and corresponds in position to the port 18' of the container 12. The extended end of conduit 38' is connected to a suitable storage container for the pumped liquid or connected to further processing machinery not forming a specific part of the present invention.

Port 36' of the drain tank 28' is positioned in the uppermost portion of the drain tank 28' and is connected to a conduit 41 Conduit 38' has interposed therein, between the outlet port 34' and the storage container for the liquid being pumped, a one-way check valve generally designated 42. The check valve 42' is similar to check valve 30' and is of the type wherein liquids will only pass from the container 28' to the receptacle for storing or processing of the liquid being pumped.

End 65 of conduit 40' is connected to a trap 61 similar in construction to trap 35 hereinbefore described. Trap 61 is provided with a lower drain conduit 63 provided with a one-way check valve assembly 65 which may be of the form and construction of check valve assembly 43 of trap 35.

A conduit 67 is attached to the upper end of trap 61 and is provided with a one-way float type check valve generally designated 69. The check valve 69 is like check valve 49 of trap 35 and prevents liquids from flowing from the trap 61 to the solenoid-actuated timer controlled valve means 46 in the event the pump timer control is not properly adjusted and overflow of the liquid being pumped fills the trap 61.

The timer control valve means 46 includes a solenoidactuated three-way valve with the solenoid having connection to an electrical circuit which may be idential in form with the electrical circuit 48 illustrated in detail in FIG. 2 of the drawings. One port of the three-way valve is connected to a source of vacuum V through conduit 50" while at the other position of the three-way valve means 46', the container 28', via the trap 61, is connected to atmospheric pressure through conduit 52. With this arrangement, the container 28 is alternately connected to the source of vacuum and then to the atmosphere as described with reference to FIG. 2 of the drawings.

One-way check valves 30' and 42' in this form of the invention may be identical in form and construction to their counterpart one-way check valves 30 and 42 of the form of the invention illustrated in FIG. 1.

The solenoid control valve 29 hereinbefore described may be connected to an electronic timer identical in form with that described in FIG. 2 of the drawings or, where desired, the timer for the solenoid control valve 29 may be of the conventional synchronous motor operated microswitch type providing, for example, a one-second interval on and a one-second interval 01f cycle of operation. However, the electronic timer of the type shown in FIG. 2 is preferred as it provides the operator with a substantially greater range of settings. Fixed interval timers, however, are inexpensive, easy to repair, and do a reasonably satisfactory job when properly set.

In operation of the milk cycle for the form of the invention illustrated in FIG. 3, conduit 25 is connected to a source of milk and manual valve 27 is opened. Valve 23 is set to provide the proper rate of flow of fluid through the system and conduits 50' and 22 are connected to a source of vacuum of about 15 inches of mercury and the timer mechanism for the solenoid-actuated valve means 46 is energized by 115 volt alternating current. At the beginning of the cycle, the solenoid of the solenoid-actuated valve means 46' is unenergized whereby a reduced pressure is drawn on both of the containers 12' and 28.

The vacuum applied to the system draws milk through the conduit 25, the conduit 20' about the manual flow control valve 23 and into the container 28 about one-way flow control check valve 30'. Since a vacuum is being drawn on the drain tank 28', the freely suspended resilient member in check valve 42' is in sealed engagement with the circular opening 56' of the valve and the drain tank 28' begins to fill with milk. The freely suspended resilient member of check valve 65 is also against its cooperating seat and is held there by the vacuum being drawn through the trap 61 whereby if the timing cycle is off and the drain tank 28' fills completely, the excess milk would be collected within the trap 61.

At a predetermined time interval depending upon the setting of the electronic timer for the solenoid control valve 46', the valve 46' cuts ofif the supply of reduced pressure to the drain tank 28' and connects the conduit 4%) of the drain tank 28' to the atmosphere through conduit 52. As soon as the drain tank 28 is vented to atmosphere, the freely suspended resilient member of the check valve 42' is urged downwardly whereby the milk in the drain tank 28 flows therefrom. Similarly, the freely suspended resilient member of the check valve 65 of the trap 61 also moves downwardly discharging any milk collected in the trap 61 into a suitable container. Simultaneously, the vacuum being drawn on the container 12' via the conduit 22 and the trap 35 urges the freely suspended resilient member in check valve 30 into engagement with its circular seat preventing further flow of milk from the conduit 20 into the drain tank 28. This portion of the cycle continues as the relay for the automatic timer connected to the solenoid-actuated valve 46' remains unenergized. The period of time in which this portion of the cycle remains in operation is such that the drain tank 28' may completely discharge its collected milk. Then the drain tank 28' is again connected to a vacuum and the milking cycle hereinabove described repeats whereby milk being drawn into the drain tank 28' via the conduit 20' and from the container 12' via conduit 21.

When it is desired to wash the apparatus, manual control valves 27 and 37 are closed, the solenoid control valve 29 is connected to energize its timing mechanism, the caps 33a, b and c are removed from the nipples 31a, b and c and the milker units are connected thereto with the lower ends of the milker units being placed in a tank containing the washing solution. When the main valve 46' is energized, washing fluid is drawn by the vacuum through the milking units and their milk lines into the conduit 20'. By pre-setting the non-energized time of the air injector solenoid valve 29, the quantity of water drawn into the line 20 is controlled for a given vacuum and number of milking units. When the desired amount of cleaning fluid is in the line, the air injector valve is energized by its timer and the cleaning solution flows through the milk lines in a slug form, much like a piston in a cylinder. When the air injector valve is again d e-energized, another slug of water enters the system. When the high velocity slugs of cleaning solution traveling through the conduit 20' arrive at the control valve 23, some of it flows into the container 12', through the line 22' and into the trap 35 while the other portion flows in the opposite direction through valve 23 into the drain tank 28' and its trap 61. When the timer for the solenoid control valve 46' closes, venting this portion of the system to atmosphere, the cleaning fluid in both of the spheres 12' and 28', and in both of the traps 35 and 61 drains back into the wash solution tank. When vacuum is again applied to the drain tank 28', the one-way check valves 43, 42' and 65 again close and the washing cycle is repeated. The high speed flow of the cleaning fiuid slugs through the system creates substantial turbulence providing very eflicient washing with substantially little washing fluid. It has been found that during a normal washing cycle, the slugs of cleaning fluid are traveling at about 25 to about 35 miles per hour when the washing solution reaches the drain tank 28. Normally, the timer for the solenoid control valve 46' is adjusted such that the drain tank 28' is filled with washing fluid, thus insuring good washing action in its upper neck portion.

From the foregoing description of the washing cycle, it will be apparent to those skilled in the art that very efficient Washing is provided with a minimum of Washing fluid. It has been found that with six milker units and approximately 300 feet of l /z-inch glass line in a system, the system may very efiectively be washed by about 14 gallons of washing solution for each wash cycle.

While the improved washer has been described primarily with reference to FIG. 3 of the drawings, it will be apparent to those skilled in the art that the principles of the air injector washing system may be readily applied to the form of the invention illustrated in FIG. 1 by connecting an air injector valve mechanism 29 and the branch conduits 31a, 31b and 310, etc. to the milk line 20 for sphere 12 of the form of the invention shown in FIG. 1.

I claim:

1. A vacuum type milk releaser comprising an integral glass receiving container and drain tank; said container having an upper and lower end, first glass conduit means integral with the upper end of the glass container and adapted to be connected to a source of reduced pressure, second glass conduit means integral with said container and adapted to be connected to a source of milk, said glass drain tank having an upper and lower end, third glass conduit means integral with the lower end of the receiving container and said drain tank, fourth glass conduit means integral With the upper end of the drain tank and adapted to be connected to a timer controlled valve and source of reduced pressure, fifth glass conduit means integral with the lower end of the drain tank, a constriction in said third and fifth glass conduit means defining a circular opening therethrough having smooth rounded edges, a freely suspended spherical resilient member having a diameter larger than the circular openings in said third and fifth conduit means and adapted to contact the respective circular openings, means projecting into said third and fifth glass conduit means to support the respective spherical members at a position below their position of contact with the circular openings, thereby providing a check valve in said third and fifth glass conduit means against upward flow of milk.

2. The milk releaser defined in claim 1 including means for introducing air into said second glass conduit means comprising a control valve in said second glass conduit means between the source of milk and the container for venting said second glass conduit means to atmosphere, an actuator for said control valve, timer means for alternately energizing the actuator to alternately open and close said second control valve during washing of the pump, and further means in said second glass conduit means between said control valve and the container for connecting said second glass conduit means to a source of washing liquid.

3. The milk releaser defined in claim 1 including a constriction in said first and fourth glass conduit means defining a circular opening therethrough having smooth rounded edges, a freely suspended spherical resilient member having a diameter larger than the circular openings in said first and fourth conduit means and adapted to contact the respective circular openings, means projecting into said first and fourth glass conduit means to support the respective spherical members at a position below their position of contact with the circular openings, thereby providing a check valve in said first and fourth glass conduit means against upward flow of milk.

References Cited by the Examiner UNITED STATES PATENTS 2,786,445 3/1957 Golay 11914.07 2,818,076 12/1957 Erling 134169 2,871,821 2/1959 Golay 11914,07 3,044,443 7/1962 Baum 11914.07

FOREIGN PATENTS 12,6 19/ 28 4/ 1928 Australia.

168,818 8/ 1934 Switzerland.

ABRAHAM G. STONE, Primary Examiner.

ANTONIO F. GUIDA, T. GRAHAM CRAVER,

Examiners. 

1. A VACUUM TYPE MILK RELEASER COMPRISING AN INTEGRAL GLASS RECEIVING CONTAINER AND DRAIN TANK; SAID CONTAINER HAVING AN UPPER AND LOWER END, FIRST GLASS CONDUIT MEANS INTEGRAL WITH THE UPPER END OF THE GLASS CONTAINER AND ADAPTED TO BE CONNECTED TO A SOURCE OF REDUCED PRESSURE, SECOND GLASS CONDUIT MEANS INTEGRAL WITH SAID CONTAINER AND ADAPTED TO BE CONNECTED TO A SOURCE OF MILK, SAID GLASS DRAIN TANK HAVING AN UPPER AND LOWER END, THIRD GLASS CONDUIT MEANS INTEGRAL WITH THE LOWER END OF THE RECEIVING CONTAINER AND SAID DRAIN TANK, FOURTH GLASS CONDUIT MEANS INTEGRAL WITH THE UPPER END OF THE DRAIN TANK AND ADAPTED TO BE CONNECTED TO A TIMER CONTROLLED VALVE AND SOURCE OF REDUCED PRESSURE, FIFTH GLASS CONDUIT MEANS INTEGRAL WITH THE LOWER END OF THE DRAIN TANK, A CONSTRICTION IN SAID THIRD AND FIFTH GLASS CONDUIT MEANS DEFINING A CIRCULAR OPENING THERETHROUGH HAVING SMOOTH ROUNDED EDGES, A FREELY SUSPENDED SPHERICAL RESILIENT MEMBER HAVING A DIAMETER LARGER THAN THE CIRCULAR OPENINGS IN SAID THIRD AND FOURTH CONDUIT MEANS AND ADAPTED TO CONTACT THE RESPECTIVE CIRCULAR OPENINGS, MEANS PROJECTING INTO SAID THIRD AND FIFTH GLASS CONDUIT MEANS TO SUPPORT THE RESPECTIVE SPHERICAL MEMBERS AT A POSITION BELOW THEIR POSITION OF CONTACT WITH THE CIRUCLAR OPENINGS, THEREBY PROVIDING A CHECK VALVE IN SAID THIRD AND FIFTH GLASS CONDUIT MEANS AGAINST UPWARD FLOW OF MILK. 